Drop-testing device



Get. 26, 1948. J. R. ToMLlN DROP-TESTING DEVICE `5 sheets-sheet 2 Filed June l, 1945 rmeans therefor, which canbe `tion hereinafter Patented Oct. 26, 1948 2,452,084 Fler.

y2,452,084 onor-TESTING DEVICE John R. Tomlin, Arlington, Va.;

Ralph E. Remington administrator of said John R. Tomlin,

deceased application June 1, 1945, serial no. 597,054

14 Claims.

(Granted under ythe act of amended April 30, 1928;

This invention describedherein, if patented, may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to ak machine for testing materials by dropping them from a predetermined height, and more particularly to a device which releases the object automatically after it has been lifted to thedesired height,`and permits it to drop vertically to the bottom. V

Crates, bags, and other containers and objects are customarily tested by dropping them repeatedly from an elevated plane. The quality of the object is then determined by thenumber and height of drops which it is able to withstand before breaking. Diiculties in this method of testing have been encountered when dropping the object from elevated platform, because of lack of precision of the releasing means which frequently cause the objectto deviate from a straight vertical path. In the conventional droptesting device of the elevator type itis necessary to arrest the platform after it `has reached the predetermined height and vthen by a separate manipulation release the object therefrom; this is ytime-consuming and a source of inaccuracies.

It is an object of my invention to provide a drop-testing machine which automatically vreleases the test ob-ject when the elevator platform reaches a predetermined height on its upward travel. ,f

Another object of my inventionis to provide load-releasing means which cause the test object to drop in an accurate vertical path.

Still another object is t'o provide a drop-testing machine capable of accomplishing the foregoing 4objects by simple mechanical means.

A further object is to provide an arrangement causing the platform to revert automatically to load-supporting position after discharge of the load.

A further object of my invention is to provide an elevator platform and automatic releasing structed from low-priority materials, and can be easily incorporated in lconventional drop-testing machines of the winch-operated elevator YDB- It is also an object of this invention to yprovide a drop-testing device of generally improved construction whereby the device will be simple,v durable and inexpensive in construction, as well as convenient, practical, serviceable and efficient in its use.

VWith the foregoing and other objects in view, which will appear as the description proceeds, the invention resides in the combination and arrangement of parts, and in details of construcdescribed and claimed, it being understood that various changes in form, proeconomically conheight.

.of the element `other suitable means.

March 3, 1883, as 370 0. G. 757) portion, and minor details of construction may be made within the scope of the claims without departing from the spirit or sacrificing any advantages of the invention. For a complete disclosure of l,the invention, a detailed description ofl it will now be givenin connection with the accompanying drawings'formmg a part'of the specification, wherein: A Figure 1 is a perspective "view of a drop-'testing machine in accordance withy myinvention. Figure 2 is an elevational view of the elevator platform forming part of the machine illustrated in Figure 1, viewed from line '2V-v2 on Figure 1.`

Figure 3 is an edge view corresponding toFigure 2. Figure ll,` which corresponds to" Figure 2, shows in elevation the elevator platform at the instant of load release (in solid lines) and immediately after load release (in broken' lines).

Figure 5 is a detailed 'perspective view ofthe movement synchronizing and platform locking and releasing means of the machine'illustrated in Figure 1.

Figure 6 shows in perspective view the vload locking and releasing latch'and the bracket mounting therefor,` and Figure `|7 'is a top view of lthe assembled load locking and Yreleasing means, as viewed from line 'I-'I of Figure v1.

The principle of the load release in accordance with my invention consists of an elevator platform formed by two trap doors opening atv the center of the platform, a link connection'between' the l`two doors for opening them simultaneously, and a release latch actuated .by a trip pin protruding from an elevator upright at a predetermined The preferred embodiment of my invention comprises an elevator base II, two upright guide members I2, I2', an electric winch' hoist I3, con-v trolled by a hand operated limit switch, I'3A, and a wire cable I4. -One guide member I2 is provided with a vertical element I5 having spaced apart holes I6 at intervals of one half Afoot or other predetermined intervals.l In slidable frictional engagement with each hole `I6 is an obstruction in the form of a horizontal retractable trip pin I1. When in nolnfoperative retracted position, the trip pins` IIare flush with'the front I5 and protrude from the rear of the element. To release the load from vthe desired height, the pin corresponding tojthat selected release height is pushed outward byhand or with the aid of a pointer stick (notshown') or A vertically slidable obstruction (not shown) .or other equivalent means may be substituted for trip pins/I1 y The elevator platform comprises va frame I8 suspended from cross beam' I 9, which slides'in guide members I 2, I2',V by hangers 20 which are spaced apart by al pairof crossv braces,2l, ,2`I. The floor of the platform is formed by load-supreaches the desired height,

porting members or platform decks, 22, 23, hingedly connected to frame |8 by a pair of rods 24,

24', the ends of which are sunk in frame I8.

or doors open from the thus forming a double lever 25 has its fulcrum secured to the door 22 or its pivot 4' 21 for the purpose of synchronizing the movements of doors 22 and 23. A linkage consisting of short arms 26 and 26" and link 21?` braces decks or doors 25, arm 25, and link 2'|.' The outer terminal of the long arm of bell crank lever `25 operably supportsa roller 28, and extends upwardly to the when decks or doors 22 this position the roller 28 level ofv cross brace 2| and 23 are closed. In

rests against load locking and releasing latch 29. 'Ihe'latchy 29 is attached to cross brace 2| by meansof vbracket 30, and is adapted to slide vertically in slots 3 ,.'3 of said bracket 30|. Slots 3|, 3|', are preferably reinforced by slotted backing plates 32, 32' protruding from latch 29 serve as 'guides in said slots 3|, 3| and backing plates 32, 32. Latch 29 has vertical sliding movement within an open guide housing defined by lugs `34, 34 and 35, 35 mounted on the upper surface of bracket 30 above slots 3|, 3|. A lever 35 is suitably located between lugs 34 and 34', and this lever fulcrums around pin 31. The ears of, lugs 34,-34' form supports or bearings for-pin 31. The short arm of lever 36 is connected with the upperend of latch 29vby a connecting pinv33. The long arm of lever 36 extends substantially horizontally beyond the cross brace 2| and beyond holes I6.

`When the elevator platform travels upward, the non-retracted protruding trip pin I1 engages the long arm of lever 33 when the platform causing the short armfof lever to lift latch 2S, and thereby release the long arm of bell crank lever 25. The weight of the load Vbearing on decks or doors 22, 23 causes the upper end ofbell crank lever 25 to swing downwardly in an arc as shown in Figure 4, and decks '.22 and 23 open up to the position illustrated in broken lines of Figure 4, causing the load 39 placed thereon (Figure 2) to drop in a vertical path onto `thebase y After .the load 39 has been released, avspring `4|l,.bent at right angles, and secured .to frame |8 bears against the short arm of bell crank lever 25 near its fulcrum, thus forcing .decks 22 and 23 back towards theirnormal horizontal-position. A helical spring or counterweights (not shown) may be substituted for flat spring 4D. AThe complete closing of decks 22 and 23 takes place when they come in contact with base Simultaneously the long arm oflever 25 swings upwardly, the roller 28 traveling `past the bevel-shaped lower portion of latch 29, and returns towards the locked position. u The long arm of lever 36 consists of two parts joined by anelbow or rule joint 4|, which permits the outer end to tilt upwardly when encountering an obstacle, thus enabling lever .3B to travel past trip pin l1v during the downward travel of the elevator platform.

The base is provided `with a cut-outorrecess (-not shown) for the reception of the portion of 5 the link structure v25, 21 which extends belowjthe lower level of decks 22 and 23.

;i and a pair of studs 33, 33' f' 22, 23at the side opposite lever scription that a drop testing machine equipped with automatic platform locking and releasing means in accordance with my invention is capable of modifications in addition to those illustrated, all within the spirit of my invention. The scope of my invention is therefore deemed to be limited by the appended claims only.

I claim:

l. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: two platform decks pivoted at opposite sides of said platform, movement synchronizing means between said platform decks, and platform locking and load releasing means comprising an arm rigidly secured to one platform deck, a latch engaging said arm, and latch releasing means comprising selectively retractable trip pins spaced apart on one of said uprights and a pivoted latch arm to be actuated by a retractable but non-retracted trip pin.

2. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platforn-l'between said uprights: a plurality of vertically spaced, selectively retractable obstructions horizontally supported parallel to one of said uprights, a pair of pivoted decks forming the floor of .said platform, synchronizing means permitting said decks to swing downwardly at the center of said platform, means for locking said platform decks in load supporting position, and release means for said platform decks actuated by a retractable but non-retracted obstruction placed in the path of said last-named means at a predetermined height.

3. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a plurality of vertically spaced, selectively retractable obstructions horizontally supported parallel to one of said uprights, a pair of pivoted decks forming the oor of said. platform, synchronizing means permitting said decks to swing downwardly at the center of said platform, means for locking said platform decks in a horizontal position, release means for said platform decks actuated by a retractable but nonretracted obstruction, and means urging said decks towards the horizontal position when said decks are swung downwardly. V4. In a drop testing machine of thetype comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a pair of pivoted decks forming the oor of said platform, means for synchronizing a central downward swinging movement of said decks, said synchronizing means comprising two arms, each arm being rigidly secured to one of said decks, and a link connecting said arms, and means for locking and releasing said decks, said means comprising a latch releasably engaging one of said arms, and a plurality of vertically spaced lmembers selectively positionable in the path of said latch at predetermined heights relative to the vertical path of said elevator platform and adapted to engage and actuate said latch forreleasing said decks.

5. In a drop testing machine of the. type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a plurality of vertically spaced, selectively retractable obstructions horizontally supported parallel to one of said uprights, a pair of swinging decks forming the floor of said platform, an arm rigidly secured-to and extending upwardly from one of said decks, a latch releasably engaging said arm, and latch releasing means to be actuated by a retractable but nonretracted obstruction placed in the path of said last-named means at a predetermined height.

6. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a retractable obstruction associated with one of said uprights, a pair of swinging decks forming the floor of said platform, an arm rigidly secured to and extending upwardly from one of said decks, a vertically slidable latch engaging said arm, and a pivoted lever engaging said latch and extending outwardly to a point permitting contact with said obstruction.

7. A device according to claim 6, wherein said lever comprises an outer and an inner section and a connecting elbow joint permitting upward tilt of said outer section.

8. In a drop testing machine of the type com prising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: spaced parallel retractable obstructions associated with one of said uprights, a pair of swinging decks forming the floor of said platform, a bell crank lever rigidly secured at its fulcrum to one of said decks, a latch releasably engaging one end of said bell crank lever, latch releasing means to be actuated by a protruding one of said obstructions, an arm rigidly secured to the other deck, and a link connnecting said arm and the other end of said bell crank lever.

9. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a plurality of vertically spaced, selectively retractable obstructions horizontally supported parallel to one of said uprights, a platform frame, a pair of downward swinging decks for raising and lowering said platform between said uprights: a pair of pivoted decks forming the floor of said platform, synchronizing means permitting said decks to swing downwardly at by one of said uprights and release means for said platform decks actuated by a retractable but non-retracted obstruction placed in the path of said release means at a predetermined height.

11. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: two platform decks pivoted at opposite sides of said platform, movement synchronizing means between said platform decks, and platform locking and load releasing means comprising an arm rigidly secured to one platform deck, a latch for engaging said arm, and latch releasing means comprising a trip member associated with one of said uprights and a pivoted latch arm to be actuated by said trip member.

12. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a plurality of vertically spaced retractable obstructions selectively positionable at predetermined heights relative to the vertical path of said elevator platform, said obstructions being horizontally supported by one of said uprights, a pair of pivoted decks forming the floor of said platform, synchronizing means permitting said decks to swing downwardly at the center of said platform, means for locking said platform decks in a horizontal position, releasing means for said platform decks actuated by a retractable but non-retracted obstruction placed in the path of said releasing means at a predetermined height, and means urging said decks towards the horizontal position when said decks are swung downwardly.

'13. A drop testing machine including a vertically movable elevator, separate load-supporting members pivotally supported on the elevator and movable about their pivots from load-supporting position to load-releasing position, means for synchronizing the movement of the load-supporting members, means for locking the said supporting members in load-supporting position, means for releasing the said locking means, and a plurality of vertically spaced members selectively positionable in the path of said releasing means at predetermined heights relative to the vertical movement of the elevator and adapted to engage the said releasing means, whereby the load-supporting members are released to drop the load at a selected height.

14. In a drop testing machine of the type comprising an elevator platform, uprights, and means for raising and lowering said platform between said uprights: a retractable obstruction associated with one of said uprights, a pair of swinging decks forming the iioor of said platform, an arm rigidly secured to and extending upwardly from one of said decks, a vertically slldable latch releasably engaging said arm, said latch being beveled opposite its arm-engaging face to permit the return of said arm from a released position to an arm-engaged position, and a pivoted lever engaging said latch and extending outwardly to a point permitting contact with said obstruction.

JOHN R. TOMLIN.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATESy PATENTS Number Name Date 746,200 Thomas Dec. 8, 1903 855,784 Jones June 4, 1907 1,491,990 Kindervater Apr. 29, 1924 1,604,089 Topfl Oct. 19, 1926 1,868,727 Constable .l July 26, 1932 

